8．センチネルノード診断

Sentinel Lymph Node Diagnosis for Lung Cancer

センチネルノード（sentinel node：SN）とは悪性腫瘍からのリンパ流が最初に到達するリンパ節のことである．SNに転移がなければ，それ以遠のリンパ節には転移が生じないとするのがSN理論である．この理論が成立する場合，SNに転移がなければ広範なリンパ節郭清が不要になる．癌の個別化治療の考えとともに，乳癌や悪性黒色腫に対する手術でリンパ節郭清省略に臨床応用されている．最近では胃癌，食道癌，大腸癌，頭頸部癌，婦人科癌など幅広い領域での臨床応用が検討されつつある．

Many researchers have reported that the sentinel node （SN） theory has been established for lung cancer. However, sentinel node navigation surgery （SNNS） has not yet become a routine medical procedure in lung cancer surgery. SN identification is important for efficient retrieval of micrometastases. Methods for identifying SNs include the dye method and the radioisotope （RI） method, but methods such as the indocyanine green （ICG） method, computed tomographic lymphography （CTLG）, and the magnetic method are also being studied. More careful surgical adaptation is required for reduction surgery for early lung cancer, and rapid intraoperative diagnosis is frequently used. SN lymph nodes may be used as an indicator for selecting lymph nodes to be diagnosed intraoperatively. SN identification is considered an important method for ensuring that reduction surgery is curative. Furthermore, if overlooking lymph node metastases can be avoided by using intraoperative rapid diagnosis of micrometastases, we believe that the safety of reduction surgery will be enhanced. In addition, SN identification provides a theoretical basis to support the omission of lymph node dissection. Future developments of SN research and technology are expected.